If the temperatures of the source and sink are increased by the same amount, the efficiency of the e

Question

If the temperatures of the source and sink are increased by the same amount, the efficiency of the engine\

Professor PC Thomas Classes · Answer

$\eta=\frac{\mathrm{T}_{1}-\mathrm{T}_{2}}{\mathrm{~T}_{1}}$. When $\mathrm{T}_{1}$ and $\mathrm{T}_{2}$ are increased by the same amount the numerator remains the same and the denominator increases. So the value of $\eta$ decreases. On the other hand if $\mathrm{T}_{1}$ and $\mathrm{T}_{2}$ are decreased by the same amount the value of $\eta$ will increase.